Fracture complexity operation control

Abstract

Aspects of the subject technology relate to systems, methods, and computer-readable media for controlling a hydraulic fracturing job. Diagnostics data of a hydraulic fracturing completion of a wellbore can be received. A fracture formation model that models formation characteristics of fractures formed through the wellbore into a formation surrounding the wellbore during the hydraulic fracturing completion with respect to surface variables can be accessed. A subsurface objective function of fracture complexity can be selected from a plurality of subsurface objective functions for changing one or more of the formation characteristics of the fractures. The fracture formation model can be applied based on the diagnostics data to determine values of the surface variables for controlling the formation characteristics of the fractures to converge on the subsurface objective function of fracture complexity. As follows, a fracture completion plan can be formed based on the values of the surface variables.

What is claimed is: 
     
       1. A method comprising:
 receiving diagnostics data of a hydraulic fracturing completion of a wellbore; 
 accessing a fracture formation model that models formation characteristics of fractures formed through the wellbore into a formation surrounding the wellbore during the hydraulic fracturing completion with respect to surface variables of the hydraulic fracturing completion; 
 selecting a subsurface objective function of fracture complexity from a plurality of subsurface objective functions for changing one or more of the formation characteristics of the fractures by assigning a weight to the subsurface objective function for fracture complexity that is greater than a corresponding weight assigned to each of the plurality of subsurface objective functions; 
 applying the fracture formation model based on the diagnostics data to converge on the plurality of subsurface objective functions according to the corresponding weights assigned to the plurality of subsurface objective functions including the weight assigned to the subsurface objective function for fracture complexity; and 
 forming a completion plan for performing the hydraulic fracturing completion of the wellbore based on the values of the surface variables. 
 
     
     
       2. The method of  claim 1 , wherein the formation characteristics include either or both subsurface fracture geometry of the fractures during formation and growth behavior of the fractures during formation. 
     
     
       3. The method of  claim 1 , further comprising facilitating implementation of the completion plan in performing the hydraulic fracturing completion of the wellbore. 
     
     
       4. The method of  claim 1 , wherein the completion plan is a modified completion plan formed by modifying a previous completion plan for the hydraulic fracturing completion based on the values of the surface variables. 
     
     
       5. The method of  claim 1 , wherein the plurality of subsurface objective functions include one or more of an objective function for cluster efficiency, an objective function for well interference, and an objective function for one or more surface costs associated with changing one or more of the formation characteristics of the fractures during the hydraulic fracturing completion. 
     
     
       6. The method of  claim 1 , wherein the fracture complexity includes a density of the fractures per unit volume of the formation surrounding the wellbore measured by a total surface area of the fractures formed per the unit volume of the formation. 
     
     
       7. The method of  claim 1 , wherein the surface variables include one or a combination of characteristics of a perforation cluster plan, a rate at which either or both fluid and slurry is pumped during the hydraulic fracturing completion, a concentration of proppant pumped during the hydraulic fracturing completion, a viscosity of either or both the fluid and the slurry pumped during the hydraulic fracturing completion, whether to use one or more diverter stages during the hydraulic fracturing completion, and characteristics of the one or more diverter stages. 
     
     
       8. The method of  claim 1 , wherein the subsurface objective function of fracture complexity includes a volume of either or both fluid and slurry pumped during the hydraulic fracturing completion into a unit volume of the formation surrounding the wellbore during the hydraulic fracturing completion. 
     
     
       9. The method of  claim 1 , wherein the subsurface objective function of fracture complexity includes a number of microseismic events occurring per unit volume of the formation surrounding the wellbore during the hydraulic fracturing completion. 
     
     
       10. The method of  claim 1 , wherein the subsurface objective function of fracture complexity includes fracture length along a plurality of directions per unit volume of the formation surrounding the wellbore during the hydraulic fracturing completion. 
     
     
       11. The method of  claim 1 , wherein the subsurface objective function of fracture complexity includes fracture growth rate along a plurality of directions per unit volume of the formation surrounding the wellbore during the hydraulic fracturing completion. 
     
     
       12. The method of  claim 1 , wherein the diagnostics data includes microseismic data describing microseismic activity in the formation during the hydraulic fracturing completion, the method further comprising applying the fracture formation model based on the microseismic data. 
     
     
       13. The method of  claim 1 , wherein the diagnostics data includes pressure data describing pressure characteristics in a fracture system of the fractures, strain data describing strain characteristics in the formation during the hydraulic fracturing completion, and microseismic data describing microseismic activity in the formation during the hydraulic fracturing completion, the method further comprising:
 correlating the pressure data, the strain data, and the microseismic data to generate correlated diagnostics data; and 
 applying the fracture formation model based on the correlated diagnostics data. 
 
     
     
       14. The method of  claim 13 , wherein the pressure data, the strain data, and the microseismic data are correlated based on covariant data across the pressure data, the strain data, and the microseismic data, the method further comprising:
 estimating a volume of either or both fluid and slurry pumped during the hydraulic fracturing completion into a unit volume of the formation surrounding the wellbore during the hydraulic fracturing completion based on the covariant data across the pressure data, the strain data, and the microseismic data; and 
 applying the fracture formation model based on the estimated volume of either or both fluid and slurry pumped during the hydraulic fracturing completion into the unit volume of the formation. 
 
     
     
       15. The method of  claim 1 , wherein the diagnostics data includes pressure data describing pressure characteristics in a fracture system of the fractures and the pressure data include a pressure profile of a static fracture in the fracture system over time, the method further comprising applying the fracture formation model based on a decay of pressure in the static fracture over time. 
     
     
       16. The method of  claim 1 , wherein the diagnostics data includes pressure data describing pressure characteristics in a fracture system of the fractures during a hydraulic fracturing treatment of the hydraulic fracturing completion, the method further comprising dynamically applying the fracture formation model during the hydraulic fracturing treatment based on changes in the pressure characteristics during the hydraulic fracturing treatment. 
     
     
       17. A system comprising:
 one or more processors; and 
 at least one computer-readable storage medium having stored therein instructions which, when executed by the one or more processors, cause the one or more processors to perform operations comprising:
 receiving diagnostics data of a hydraulic fracturing completion of a wellbore; 
 accessing a fracture formation model that models formation characteristics of fractures formed through the wellbore into a formation surrounding the wellbore during the hydraulic fracturing completion with respect to surface variables of the hydraulic fracturing completion; 
 selecting a subsurface objective function of fracture complexity from a plurality of subsurface objective functions for changing one or more of the formation characteristics of the fractures by assigning a weight to the subsurface objective function for fracture complexity that is greater than a corresponding weight assigned to each of the plurality of subsurface objective functions; 
 applying the fracture formation model based on the diagnostics data to converge on the plurality of subsurface objective functions according to the corresponding weights assigned to the plurality of subsurface objective functions including the weight assigned to the subsurface objective function for fracture complexity; and 
 forming a completion plan for performing the hydraulic fracturing completion of the wellbore based on the values of the surface variables. 
 
 
     
     
       18. The system of  claim 17 , wherein the instructions further cause the one or more processors to perform operations comprising facilitating implementation of the completion plan in performing the hydraulic fracturing completion of the wellbore. 
     
     
       19. The system of  claim 17 , wherein the formation characteristics include either or both subsurface fracture geometry of the fractures during formation and growth behavior of the fractures during formation. 
     
     
       20. A non-transitory computer-readable storage medium having stored therein instructions which, when executed by one or more processors, cause the one or more processors to:
 receive diagnostics data of a hydraulic fracturing completion of a wellbore; 
 access a fracture formation model that models formation characteristics of fractures formed through the wellbore into a formation surrounding the wellbore during the hydraulic fracturing completion with respect to surface variables of the hydraulic fracturing completion; 
 select a subsurface objective function of fracture complexity from a plurality of subsurface objective functions for changing one or more of the formation characteristics of the fractures by assigning a weight to the subsurface objective function for fracture complexity that is greater than a corresponding weight assigned to each of the plurality of subsurface objective functions; 
 apply the fracture formation model based on the diagnostics data to converge on the plurality of subsurface objective functions according to the corresponding weights assigned to the plurality of subsurface objective functions including the weight assigned to the subsurface objective function for fracture complexity; and 
 form a completion plan for performing the hydraulic fracturing completion of the wellbore based on the values of the surface variables.